a flip-flop or latch is a circuit that has two stable states and can be used to store state information.

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NAND gate in proteus

I am trying to make a JK flip flop circuit in proteus but 2 of the nand gates does not seem to be working. There are no errors provided. Two of the 2-input nand gates does not seem to show output ...
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24 views

5-bit parallel register using RS trigger (with NotAND gate) [closed]

I have to make 5-bit parallel single-phase register using RS triggers with Not-AND gates. To check the result I use word generator and Logic Analizer. Here is my bin number 0000010001001100 which I ...
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2answers
39 views

VHDL - Flip Flop inferring on a signal

I have to design a circuit to count up to a number and return to zero. It must have a carry signal (which I named a_o in my circuit) as flag to show that the ...
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1answer
279 views

JK flip flop random start outputs

I am working on a project for college and I have to implement a sort of alarm using only MUX's and JK flip flops and a bread board. The problem I encountered is that whenever I power the whole circuit ...
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5answers
96 views

Understanding D flip flop function - what this thing does

I am trying to understand what a D flip flop does int he context of building a truth table, so I can design a synchronous divide-by-five circuit. That is, count to five and reset. I know I need 3 ...
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2answers
54 views

Unable to toggle SN74HC109

I'm a complete amateur, I've probably gotten a million things wrong with this already. I'm using an SN74HC109 dual j-k" flip-flop chip. I'm trying to toggle the led (forgot to add a resistor in the ...
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1answer
52 views

JK Flipflop design for conveyor project

I have a small project/problem I am working on. While running a conveyor belt continuously with items on it, I need to stamp every other item. I am using a photocell to detect if an item is ...
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1answer
58 views

momentary to on/off switch for 12v

I got some oem switches and I want to mod them into light switches. Here is my situation: I would like to use the oem switch since it has illumination and button that matches the car.I have already ...
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1answer
30 views

Proteus BJT Astable Multivibrator Simulation Error

I am pretty new in Proteus and made a simple flip flop circuit as shown below. When I run the simulation, the circuit does not work as intended. Both of the LEDs light up at the same time. (LEDs ...
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1answer
78 views

How do I find the Truth Table for Mealy State Machine?

This is a followup to my previous question: I have this assignment in college: You are to design a Mealy state diagram for a safety device. Assume that two debounced push-buttons, A and B, are ...
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1answer
77 views

Mealy Safety Device with 2 inputs

I have an assignment in college and I would like to ask some questions: You are to design a Mealy state diagram for a safety device. Assume that two debounced push-buttons, A and B, are available ...
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1answer
52 views

Sequence detector

I have a few questions to ask about electronics.I am studying computer science in my first year and I have a logic design course where the professor is kind of old let's say and he expects us to study ...
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3answers
139 views

Need help in understanding MUX-NOT flip-flop

I need help in doing practice problem: A MUX-NOT flip-flop (MN flip-flop) behaves as follows. If M=1 the flip-flop complements the current state. If M=0, the next state of the flip-flop is equal to ...
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1answer
35 views

Need help with pspice simulation

I made a project of monostable flip flop using 555 timer in pspice. Now I need help with simulation. Problem is that I'm just statring my adventure with pspice and I have no clue what I'm doing wrong. ...
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1answer
51 views

D flipflop in keypad

Why D flipflop is used in keypad for LCD ( U2 in schematic shown below ). Is it for buffer? unidirectional or bidirectional?
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36 views

24 Hour Counter JK Flip Flop

I'm trying to implement a 24 hour clock circuit using JK Flip Flops. I've gotten the minute part but I am having trouble designing the hours part, specifically the ones section. If it should count ...
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1answer
60 views

Mealy machine to detect sequence of 2 inputs

I have the following assignment for a project at college and I have a few questions regarding it. You are to design a Mealy state diagram for a digital lock. Assume that two debounced push-buttons, A ...
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2answers
40 views

Building circuit for n-relays using flip flops, is this the best solution?

I'm trying to build a circuit for n relays, each relay should hold it's state (ie latched). My first Idea was to use decoders, but clearly this was a bad option, since the state of the relays won't ...
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1answer
86 views

How would you make a 3-bit binary adder that adds two instead of 1?

I am trying to make an asynchronous adder that holds three bits and adds two to the number. Can someone help? A Google search shows nothing and I'm having a hard time visualizing how to make the ...
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0answers
34 views

Kmap Implementation in Electronics Workbench

I'm working in Electronics Workbench and after simplifying two of the Kmaps, I got values : Jd=1 & Kd=1 How would I implement that in the circuit? I know it looks confusing at the moment.
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81 views

LFSR Using D Flip Flops

I am fairly new to the VHDL language and I will admit that I primarily use it for educational purposes. I have been attempting to design a data encryption circuit using D flip flops. Obviously, an ...
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1answer
40 views

Help designing a serial adder [closed]

I need to build a circuit that adds two n-bit 2's complement numbers. the two numbers have to be stored in shift registers. The circuit should start with the least significant bits of each number and ...
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1answer
54 views

FSM for predesignated process (How to draw the state diagram)

let me start by saying this involves some homework problems so if you could help guide me a bit I would greatly appreciate it. I have been working with finite state machines for a bit in my course ...
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0answers
48 views

Parallel-in, parallel-out, universal shift register

I am trying build circuit of parallel-in/parallel-out universal shift register. I have found circuit in the Internet. Here it is I have tried to do this using MicroCap , but it doesn't work as ...
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42 views

Continuous Wave with flip-flops

What I'm going for is imagine 6 LED outputs, every other one on. (Off first) What I need to have happen is after I toggle on the 1 input to 1, it sets off a chain reaction, like a wave, where every ...
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1answer
58 views

Truth Table for JK flip-flop circuit?

Given a JK flip-flop circuit (using a D flip flop with a 2 by 1 MUX) how can I derive a truth table from this circuit? D = JQ' + K'Q Note: This is NOT a homework question. I just simply want to ...
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1answer
54 views

Does the output of JK Flip Flop toggle continously?

As given in most of the texts and online resources, the JK flip-flop requires a clock signal with an edge detector circuit so that the flip flop will be sensitive to the inputs only when the clock ...
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68 views

flip flop transfer function

Can same one explain me, if possible, how to get the equation of the transfer function for flip flop like the one below and hence get a plot like this
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1answer
99 views

Can someone explain to me what the 1s catching problem is in the Master Slave Flip Flop?

I have read the explanation in my textbook but I feel that they are too complex and no matter how much I try to understand it I don't seem to get what the difference is when the 1s complement occurs. ...
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1answer
51 views

How to toggle a reset in a counter made up of JK flip flops

I have been playing around with a small circuit which at the moment consists only of a counter made up of 3 JK flip flops. Like so: What I want to add is a reset input pin that will set the 3 LEDs ...
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1answer
30 views

connected d flip flop, propagation time = hold time?

When we connect two d flip flops, the propagation time and hold time have to be the same? or the propagation time have to be bigger than the hold time? I'm really confused please help!!
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2answers
237 views

Toggle two different LEDs with one T Flip flop

Imagine we have one green LED, one blue LED, power supply and resistors and grounds. We also have a switch. Can we toggle between the two different LEDs when the switch is pushed? If the blue LED is ...
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1answer
59 views

Purpose of T flip-flop in this circuit (LED)

In this circuit I try to toggle a LED on and off when a switch is pressed. Given the nature of the T flip-flop, when the switch is triggered, it toggles the clock and since T=1 always, it ...
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1answer
61 views

T-flip-flop without using a clock [closed]

Is it possible to create a T flip-flop without using a clock? I really need one, but I can't use one with a clock because it requires a signal shortener.
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49 views

Relay is not isolating properly its sorrounding circuit blocks

It turns out I've been building up an elevator for a project (at College). In general terms, everything appeared to be correct, regardless that I hadn't simulated each part. I decided to begin with ...
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3answers
451 views

Where does the power supply go in an SR Latch?

I understand how an SR Latch works: is S is 1, it will set Q to 1. If R is 1 it will set Q to 0. If both S and R are 0, the value of Q should remain unchanged (right?). So the circuit has these ...
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1answer
127 views

What is reset, preset and clear in a counter circuit?

I know this is a basic question. But I want to know the use of Reset, Preset and Clear in a Counter circuit. How do I use them? An example would be appreciated.
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4answers
246 views

ICs Powering On With Random Values

I've been prototyping a circuit for a first year university engineering project and I've been running into some problems with one section of the circuit that has really stumped me. Basically the flip ...
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1answer
61 views

Microcontrollers [closed]

Is there any other way of interfacing a push button with a LED but not directly with the micro controller? I would like to operate the LED in both method(push button as well as micro controller ...
2
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2answers
336 views

Setup Time, Hold Time - What is the underlying principle for having them?

I'm learning about setup time and hold time of a FF connected to a bus. But the textbook fails to explain exactly why are those needed in an operation. Isn't a FF always powered on and attentive to ...
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1answer
46 views

Is a D Type Edge triggered Master Slave flip flop considered a 1bit memory cell?

So in class we talked about how a D-type edge triggered flip flop is considered a 1bit memory cell. I think this is the same for a D-type latch. My question is, since a D-type edge triggered master ...
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1answer
99 views

D flip flop simulation: which simulation output is right?

I have always wondered, what is the right solution to the D flip flop when the input changes right at the rising edge of the clock? I have found two solutions of these online but have no clue which is ...
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0answers
154 views

How to create JK flip flop in proteus 8

I want to create a JK flip flop in Proteus 8.0 ISIS simulation tool. This is what I tried, but the problem with this is that the outputs Q and Q' are always zero regardless of what I set J or K. ...
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1answer
65 views

3 State Shift Register with 2-to-1 multiplexers

For a homework assignment I need to Redesign the right-shift register circuit of Figure 12-10 using four D flip-flops with clock enable, four 2-to-1 MUXes, and a single OR gate. The figure ...
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1answer
52 views

Different Vcc and input voltage into flip flop

I am building an LED matrix using flip-flops. I will have 128 rows in the matrix, so I am using 16 octal flip-flops, where all inputs to are shared and come from a microcontroller, which uses 5V ...
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2answers
89 views

Signal-driven 3 output logic gate decoder or switch?

I need to build a simple logic gate circuit such that when a single input signal or switch goes low it alternately activates one of three outputs as high. That is, every time it goes low the currently ...
2
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1answer
77 views

Combinational logic delay is greater than clock period

Suppose you have a combinational circuit between two registers driven by a clock. What will you do if the delay of the combinational circuit is greater than your clock signal? (You can’t resize the ...
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1answer
32 views

Initial state of SN74AUP2G80 dual FF

My understanding is that a basic FF will in general power-up into a meta-stable state that then resolves to either H or L (more or less quickly). My question is, does this apply to current ...
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2answers
753 views

What is the difference between registers, flip flops and latches?

I want the answer to the very basic level. I know what they mean individually, but what I am looking for is connection between them.
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0answers
59 views

Trouble analyzing this JK-Flip-Flop (negative edge triggered) timing diagram

Can someone check to see if this timing diagram for a negative-edge-triggered flip-flop looks correct? I see that as it's negative-edge triggered (bubble at clock input), and thus action occurs at ...